1. Field of the Invention
This invention relates to the field of video and motion picture camera control apparatus which include the capability of repeating camera motion.
2. Prior Art
Apparatus which control the movement of a camera utilize a series of motors and gear drives and generally may be implemented in one of three ways.
(a) JOY STICK--The camera moves in real time responding to the movement of a remote control joy stick. When a joy stick is used, the camera is always motor positioned and the incremental position data may be gathered to facilitate repeat of the motion. This type of control does not replicate "natural" camera aiming and it may be difficult for an experienced cameraman to become accustomed to this type of operation.
(b) COMPUTER CONTROL--Computers have been programmed and customized for motion control work. When computer control is used the position information is usually recorded by typing or otherwise loading coordinate information into a computer terminal. This motion control system can duplicate any motion any number of times because the motion sequence is always motor controlled and position data can be stored in non-volatile memory. The disadvantage of this type of control is that the camera movement is programmed by a computer operator on a frame by frame basis which makes it difficult to use in real time for live subjects.
(c) MOTION ENCODERS--Motion control systems have been designed which encode the position of a camera aiming device utilizing shaft encoding techniques. These incremental movements are recorded in a memory then later played back through a motor control system which attempts to reproduce the movement. A problem with this type of control is that the motor system may not be capable of the accelerations or speeds which may be needed to completely reproduce the movement involved.